Rim constructions

ABSTRACT

A rim for a pneumatic tire carcass has a pair of rim portions which are securable together to form such rim. One rim portion is integral with a wheel hub and includes a plurality of pockets or guide openings formed therein. The other rim portion includes guide members which correspond to these pockets and which are positionable therein to position the rim portions relative to each other. Apparatus for separating the rim portions with the tire carcass mounted on them is disclosed, as is apparatus for pulling the tire carcass off a rim portion after the other rim portion has been separated therefrom. In another embodiment, a pair of rim portions are assembled by positioning posts fixed on one rim portion into angled slots defined by the other rim portion, and rotating one rim portion relative to the other, the posts being drawn into the slots during such rotation to draw the rim portions together. In yet another embodiment, the tire carcass is supplied with an inner peripheral stiffener, which is seatable in a groove formed by a pair of fixed-together rimmed portions to center the tire carcass thereon. Also, another embodiment includes an annular plate and rim portions mounted in spaced relationship on either side thereof.

Grawey et al.

[ RIM CONSTRUCTIONS [75] Inventors: Charles E. Grawey, Peoria; Robert W. Untz, Hanna City; Keith E. Koch, Tremont; Charles F. Gehhardt, Decatur, all of I11.

[73] Assignee: Caterpillar Tractor Company,

Peoria, 111.

[22] Filed: Oct. 1, 1973 [21] Appl. No.: 402,268

[52] US. Cl. 152/405; 152/379; 152/396; 152/411; 301/11 CD; 301/63 DS [51] Int. Cl B60b 23/00; B60b 25/02 [58] Field of Search 152/379, 396, 402, 405, 152/411; 301/11 CD, 63, 63 DS [56] References Cited UNITED STATES PATENTS 2,106,421 l/l938 Cox 152/396 2,242,425 5/1941 Ferro 2,968,332 l/l961 Gonzales 152/405 3,006,692 10/1961 Schubert 152/405 3,063,488 11/1962 Bennett et al. 152/405 Apr. 15, 1975 [5 7] ABSTRACT A rim for a pneumatic tire carcass has a pair of rim portions which are securable together to form such rim. One rim portion is integral with a wheel hub and includes a plurality of pockets or guide openings formed therein. The other rim portion includes guide members which correspond to these pockets and which are positionable therein to position the rim portions relative to each other. Apparatus for separating the rim portions with the tire carcass mounted on them is disclosed, as is apparatus for pulling the tire carcass off a rim portion after the other rim portion has been separated therefrom. In another embodiment, a pair of rim portions are assembled by positioning posts fixed on one rim portion into angled slots defined by the other rim portion, and rotating one rim portion relative to the other, the posts being drawn into the slots during such rotation to draw the rim portions together. In yet another embodiment, the tire carcass is supplied with an inner peripheral stiffener, which is seatable in a groove formed by a pair of fixed-together rimmed portions to center the tire carcass thereon. Also, another embodiment includes an annular plate and rim portions mounted in spaced relationship on either side thereof.

8 Claims, 25 Drawing Figures PATENTEUAPR 1 1915 3.877. 504

SHEET C 2 0F 10 AXLE OR DRIVE CONNECTION PATENTEUAPR 1 51875 mmwm 1 SHEET CS0? 10 PATENTEUAPR 1 5197s SHEET EBDF 1O PATENTEDAP-a 1 51975 3,877, 504

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PATENTEBAPR 1 slzs 3.877. 504

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PATENTEDAPR 1 sirs 3. 877. 504

SHEET 1 0 HF 10 WHEEL l WHEEL STUD HOUSING RIM CONSTRUCTIONS BACKGROUND OF THE INVENTION This invention relates to rim constructions for mounting a pneumatic tire carcass, and more particularly to such rim constructions which are generally formed of two or more rim portions.

U.S. Pat. No. 3,606,921 issued to Grawey (assigned to the assignee of this application) discloses a novel, oval pneumatic tube-tire. A study of such patent reveals that, because of the particular configuration of such tube-tire, a rim used therewith must fulfill certain requirements which may not exist in the case of more conventional tires.

In general, rims for use with such a tube-tire may with advantage be of the split-rim type i.e., involving a pair of rim halves securable together to form such a rim. Such a rim structure is disclosed in U.S. Application Ser. No. 283,375, now U.S. Pat. No. 3,802,744 also assigned to the assignee of this application.

While such a rim has proven to be extremely effective in use, it will be understood that a variety of rim configurations suitable for use with such tube-tire may be desired, each providing its own particular advantage, which may be of great use in the particular application of the tube-tire.

Of general interest in this area are U.S. Pat. No. 689,247 to Tillinghast, U.S. Pat. No. 1,320,999 to Baker, U.S. Pat. No. 1,595,335 to Atkins, U.S. Pat. No. 2,067,545 to Ricketts, Jr., U.S. Pat. No. 2,224,066 to Shore, U.S. Pat. No. 2,308,959 to Brink, U.S. Pat. No. 2,559,975 to Lange, et al., U.S. Pat. No. 2,713,373 to Daugherty, U.S. Pat. No. 2,720,240 to Bourdon, U.S. Pat. No. 2,860,683 to Smith, U.S. Pat. No. 3,047,041 to Battasso, et al., U.S. Pat. No. 3,090,456 to Blenkle, U.S. Pat. No. 3,329,192 to Roque V, U.S. Pat. No. 3,597,001 to Morford, et al., U.S. Pat. No. 3,610,694 to Bradley. and German Pat. No. 1,176,013.

SUMMARY OF THE INVENTION It is an object of this invention to provide rim constructions which are especially suitable for use with tube-type beadless tires such as those described in U.S. Pat. No. 3,606,921, mentioned above.

It is a further object of this invention to provide rim constructions which, while fulfilling the above object, are suitable for the intended use, meanwhile being relatively simple in construction and design.

Broadly stated, the invention comprises a rim assembly for a pneumatic tire carcass, comprising a first annular rim portion defining at least one guide pocket, and a second annular rim portion. A guide member is fixed to the second rim portion and positionable in the guide pocket to position the first and second rim portions relative to each other as they are brought together. Further included are removable means for fixing the so positioned first and second rim portions together, the rim portions when so fixed together forming a rim for the pneumatic tire carcass. Broadly stated, the invention further comprises a rim assembly for a pneumatic tire carcass comprising a first annular rim portion defining a plurality of angled slots, and a second annular rim portion. A plurality of posts are fixed to the second rim portion, and correspond to the angled slots. Such posts are positionable so that each post is disposed in a slot, the slots being angled so that rotation between the first and second rim portions in one direction draws the posts disposed in the slots more deeply into the slots and draws the first and second rim portions together. Means are included for selectively preventing rotative motion between the first and second rim portions upon drawing of the first and second rim portions together, so that the first and second rim portions are fixed together, the rim portions when so fixed together forming a rim for the pneumatic tire carcass. The invention still further comprises a rim assembly for seating and substantially centering a pressurized tire carcass of oval cross-section, comprising first and second annular rim portions, and means for securing the first and second rim portions together to form a rim for the pneumatic tire carcass. The first and second rim portions define first and second annular groove portions which lie adjacent each other to form an annular groove with the first and second rim portions so secured together. The tire carcass includes an inwardly extending annular portion at the inner periphery thereof and seated in the groove. Relatively stiff, substantially inextensible means are associated with the inwardly extending portion, which seat to an extent into the annular groove when the annular inwardly extending portion is so seated in the annular groove. The invention still further comprises a rim assembly for a pneumatic tire carcass comprising an annular plate. and first and second annular rim portions positionable on either side of the outer annular edge portion of the annular plate. Means are included for securing the first and second rim portions to the annular plate when the first and second rim portions are so positioned, the first and second rim portions and annular plate defining a rim for the pneumatic tire carcass.

BRIEF DESCRIPTION OF THE DRAWINGS These and other objects of the invention will become apparent from a study of the following specification and drawings, in which:

FIG. 1 is a side elevation of a rim portion of a first embodiment of rim assembly;

FIG. 2 is a sectional view taken along the line 11-11 of FIG. 1;

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4 is a side elevation of the other rim portion of the first embodiment of rim assembly;

FIG. 5 is a sectional view taken along the line V-V of FIG. 4;

FIG. 6 is a sectional view taken along the line VI-VI of FIG. 5;

FIG. 7 is a sectional view taken along the line VII- -VII of FIG. 4;

FIG. 8 is a sectional view of the first embodiment of rim assembly, showing the means for separating the rim portions;

FIG. 9 is a sectional view similar to that of FIG. 8, but showing the means for removing the tire carcass from one of the rim portions;

FIG. 10 is a plan view of the tire-removing means used as shown in FIG. 9;

FIG. 11 is an end elevation of the tire-removal means as shown in FIG. 10;

FIG. 12 is a sectional view of the detent device associated with the tire-removal means of FIGS. 10 and 11;

FIG. 13 is a side elevation of a rim portion of a second embodiment of rim assembly;

FIG. 14 is a sectional view taken along the line XIV-XIV of FIG. 13;

FIG. 15 is a sectional view taken along the line XV-XV of FIG. 13;

FIG. 16 is a side elevation of the other rim portion of the second embodiment of rim assembly;

FIG. 17 is a view taken along any of the lines XVII- -XVII of FIG. 16;

Hg. 18 is a view taken along, any of the lines XVIII- XVIII of FIG. 16;

FIG. 19 is a sectional view taken along the line XIX- XIX of FIG. 16;

FIG. 20 is a sectional view showing the rim portions of the second embodiment joined together;

FIGS. 21-24 are sectional views of variations of a third embodiment of rim assembly; and

FIG. 25 is a sectional view of a fourth embodiment of rim asembly.

DESCRIPTION OF THE PREFERRED EMBODIMENT Reference is made to FIGS. 1-12, illustrating a first embodiment of rim assembly 10, and associated struc- I defines pockets 14, 16, 18, 20 spaced thereabout adjacent and inwardly ofthe outer periphery of the rim portion 12. The pockets 14, I6, 18, 20 are spaced substantially 90 apart about the rim portion 12, i.e., the pockets 14, 18 are substantially 180 apart, and the pockets 16, 20 are substantially 180 apart. One of the pockets, i.e., for example pocket 14, is used to house an air fitting for a pneumatic tire carcass which will be mounted on the rim.

FIGS. 4-7 show a second annular rim portion 22 which is used in association with the rim portion 12 to form such rim. The rim portion 22 has fixed thereto a pair of guide members 24, 26 spaced substantially 180 apart. adjacent and inward of the outer periphery of the rim portion 22.

The guide members 24, 26 are positioned in the pockets 16, 20 to position the rim portions 12, 22 relative to each other as they are brought together. Thus, the pockets 16, 20 act as guide pockets. Upon the rim portions 12, 22 being brought together. a plurality of rim bolts are disposed through apertures 28 defined by the rim portion 22, and threaded into tubular members 30 (FIGS. 2 and 3) fixed to the rim portion 12, to bring the rim portions 12, 22 readily together to form the rim.

The rim portions 12, 22 define outer, conicallyshaped surfaces 32, 34 which have decreasing taper inwardly of the outer edges of the rim portions, and on which the tire carcass 36 is seated (FIG. 8). Thus, in order to normally assemble the rim, the tire carcass 36 is mounted on the rim portion 12, and rim portion 22 is applied and fitted thereto.

With the rim assembly 10 in such state as shown in FIG. 8, means are included for separating the rim portions 12, 22 upon removal of the bolts holding these rim portions 12, 22 together. Such means include a pair of force pads 38, 40 fixed to the rim portion 12 adjacent each pocket. The rim portion 22 further defines threaded apertures 42, 44 which are spaced to correspond to the force pads 38, 40. Bolts 46 are threadably fitting to these apertures, and correspond to the force pads, being positioned so that upon rotation of these bolts 46 in one direction, the bolts 46 contact respective force pads 38, 40 to urge the rim portions 12, 22

apart.

After separation of the rim portion 12, 22 by such means, further means as shown in FIGS. 9-12 are included for removing a portion of the tire carcass 36 from the rim portion 12. Such means include a bar 48 having a cross block 50 fixed to the end thereof. The block 50 defines bores 52 and 54 threaded therethrough as shown. The opposite end of the bar has fixed thereto a detent post 56 which has threaded therethrough a detent mechanism 58 as shown in FIG. 12. This mechanism 58 includes a housing 60 in which pin members 62, 64 are slidable, and held apart by a spring 66. Such pin members 62, 64 protrude to an extent beyond the detent post 56. The detent post 56 is mounted in an insert 68 associated with the tire carcass 36, the pins 62, 64 seating in depressions in the insert 68 to releasably hold the detent post 56 therein. The end of the bar 48 to which the detent post 56 is fixed of course extends into the pocket 20, the outer end extending outwardly of the pocket 20 to adjacent the pair of force pads 38, 40. A pair of puller bolts 70 are threaded through bores 52, 54, corresponding to the force pads 38, 40, and positioned so that upon rotation of the puller bolts 70 in one direction, the puller bolts 70 contact respective force pads 38, 40 for applying force to the tire carcass 36 and pulling the tire carcass portion from the rim portion 12.

A pair of guide bolts 72 are inserted through apertures 74, 76 in block 50 and threaded into tubular members 30 to guide the block 50 and bar 48 as they are being moved by the turning of bolts 70.

Shown in FIGS. 13-20 is a second embodiment of rim assembly 80 for a pneumatic tire carcass. The rim assembly includes annular rim portions 82, 84. The rim portion 82 defines a cylindrical portion 86, and the rim portion 84 also defines a cylindrical portion 88, the inner diameter of the cylindrical portion 88, being slightly larger than the outer diameter of the cylindrical portion 86. The cylindrical portion 88 of the rim portion 84 defines six angled slots 90 thereabout, at substantially 60 intervals thereabout. The cylindrical portion 86 has fixed thereto six posts 92, at substantially 60 intervals, corresponding to the placement of the angled slots 90. Each post 92 is positioned in a slot 90, it will be seen, and the slots 90 are angled so that relative rotation between the rim portions 82, 84 in one direction draws the posts 92 more deeply into the slots 90 to draw the rim portions 82, 84 together. A plurality of set screws 94 are then disposed through threaded apertures in the cylindrical portion 86, and the tips thereof are seatable in depressions 96 in the cylindrical portion 88 to prevent the rotative motion between the rim portions 82, 84. Three slots 90 spaced apart are angled at substantially 2 (FIG. 17), and three slots 90 spaced 120 apart are substantially at 5 (FIG. 18). These slots 90 are positioned in relation to each other so that the 2 angled slots provide initial drawing together of the rim portions 82, 84, and the 5 angled slots provide later drawing together of the rim portions 82, 84, as such relative rotative motion between the rim portions 82, 84 takes place, resulting in progressive drawing action upon such relative rotation.

The rim portions 82, 84 define outer conicallyshaped portions 98,100 having decreasing taper inward of the outer edges of the rim, and on which the tire carcass is seatable.

Three tabs 102 are fixed to the rim portion 82 to.

allow this rim portion to be held on a fixture if so desired as the other mating rim portion 84 is rotated into locking position.

ln FlGS. 21-24 are shown various types of rim assemblies which provide for seating and substantially centering a tire carcass 110 of oval cross-section. In FlG. 21, 98, 100 rim assembly 112 is made up of annular rim portions 114, 116 fixed to a plate 118. The rim portions 114, 116 define annular groove portions 120, 122 which are adjacent each other with the rim portions 114, 116 brought together to form an annular groove 124 with the rim portions 114, 116 so secured together. The tire carcass 110 includes an inwardly extending annular portion 126 at the inner periphery thereof, and seatable in the groove 124. In this design, relatively stiff, substantially inextensible metal wire wrap 128 is included in the inwardly extending annular portion 126. Such wire wrap 128 also seats to an extent in the annular groove 124 when the inwardly extending annular portion 126 is so seated in the annular groove 124.

The design of FIG. 22 is similar to that of FIG. 21, but with the substitution of substantially flat, elongated plate means 130 for the wire wrap 128. The plate means 130 may with advantage be a plurality of metal members embedded in the inwardly extending annular portion 126.

FlG. 23 shows yet another design of this type. As shown therein, the plurality of metal members 132 are of T-shaped cross-section, each member 132 being partially embedded in the inwardly extending annular portion 126, and having a portion extending therefrom and in contact with the rim. Such contact provides means for dissipating heat from the tire during operation thereof. V

FIG. 24 shows yet another design of this type. In such FIG. 24, the groove 134 is much smaller in crosssection than in the previous embodiments, as is the in wardly extending annular portion 136 which seats therein. A plurality of metal members 138 are embedded in such portion 136 as shown, these being of generally square cross-section as shown.

In each embodiment, the rim portions define outer conically-shaped surfaces having decreasing tapers inwardly of the outer edges of the rim and toward the groove thereof, on which the tire carcass 110 is seated.

In FIG. is shown another embodiment of rim assembly 140. Such rim assembly includes an annular plate 142, and annular rim portions 144, 146 positionable in spaced relationship on either side of the annular plate 142. A plurality of tap members 148 are fixed to the rim portion 144, and are positionable along the outer annular edge portion of the annular plate 142 with the rim portion 144 so positioned. A plurality of tab members 150 are fixed to the rim portion 146, and are positionable along the outer annular edge portion of the annular plate 142 with the rim portion 146 so positioned. A plurality of securing bolt means are included for securing the tab members 148, 150 to the annular plate 142 as shown. Such securing bolt means comprise a plurality of securing bolts 152, each disposed through an aperture in a tab member 148, an aperture in the annular plate 142, and an aperture in a tab member 150. Nuts 154 are threaded onto these securing bolts 152 and tightened to complete the rim assembly 140.

What is claimed is:

.1. A rim assembly for a pneumatic tire carcass comprising: a first annular rim portion defining at least one guide pocket; a second annular rim portion; a guide member fixed to the second rim portion and positionable in the guide pocket to position the first and second rim portions relative to each other as they are brought together; removable means for fixing the so positioned first and second rim portions together, said rim portions when so fixed together forming a rim for said pneumatic tire carcass; and means for separating the first and second rim portions upon removal of the means for fixing the so positioned first and second rim portions together comprising a plurality of force pads fixed to the first rim portion, and a plurality of corresponding boltsthreadably associated with the second rim portion and positioned so that upon rotation thereof of one direction, said bolts contact respective force pads and urge the first and second rim portions apart.

2. A rim assembly for a pneumatic tire carcass comprising: a first annular rim portion defining at least one guide pocket; a second annular rim portion; a guide member fixed to the second rim portion and positionable in the guide pocket to position the first and second rim portions relative to each other as they are brought together; and removable means for fixing the so positioned first and second rim portions together, said rim portions when so fixed together forming a rim for said pneumatic tire carcass, wherein the first rim portion defines a second pocket, and further comprising a second guide member fixed to the second rim portion and positionable in the second pocket to position. along with the first-mentioned guide pocket and firstmentioned guide member, the first and second rim portions relative to each other as they are brought together, wherein the first and second guide pockets are defined adjacent and inwardly of the outer periphery of the first rim portion substantially apart, and the first and second guide members are fixed to the second rim portion adjacent and inwardly of the outer periphery of the second rim portion, and means for separating the first and second rim portions upon removal of the means for fixing the so positioned first and second rim portions together comprising a plurality of force pads fixed to the first rim portion, and a plurality of corresponding bolts threadably associated with the second rim portion and positioned so that upon rotation thereon in one direction, said bolts contact respective force pads and urge the first and second rim portions apart.

3. The rim assembly of claim 2 wherein the plurality of force pads comprise a pair of force pads fixed to the first rim assembly adjacent each guide pocket.

4. The rim assembly of claim 3 wherein the first and second rim portions define outer conically-shaped surfaces having decreasing taper inward of the outer edges of the rim, and on which the tire carcass is seatable.

5. The assembly of claim 4 and means for removing a portion of a seatable tire carcass from the first rim portion after separation of the first and second rim portions, with the tire carcass remaining on the first rim portion, comprising a bar one end of which extends into one of the pockets and which is connectable to the tire carcass therein, the other end extending outwardly of the pocket to adjacent the pair of force pads associated with that pocket, and means connected to the force pads and the end of the bar adjacent the force pads for selectively applying force to the tire carcass through the bar, to pull the tire carcass portion from the first rim portion.

6. The rim assembly of claim wherein the means connected to the force pads and the end of the bar adjacent the force pads comprise a block fixed to the end of the bar adjacent the force pads, and a pair of puller bolts threadably connected through the block and corresponding to the pair of force pads, and positioned so that upon rotation of the puller bolts in one direction, said puller bolts contact respective force pads and pull the tire carcass portion from the first rim portion.

7. A rim assembly for a pneumatic tire carcass comprising: a first annular rim portion defining at least one guide pocket; a second annular rim portion; a guide member fixed to the second rim portion and positionable in the guide pocket to position the first and second rim portions relative to each other as they are brought together; and removable means for fixing the so positioned first and second rim portions together, said rim portions when so fixed together forming a rim for said pneumatic tire carcass, and means for removing a portion of a seated tire carcass from the first rim portion after separation of the first and second rim portions, with the tire carcass remaining on the first rim portion, comprising a bar one end of which is connectable to the tire carcass, the other end extending therefrom, and

means associated with the extending end of the bar ahd first rim portion for selectively applying forceto the bar and tire carcass through the bar to pull the tire portion from the first rim portion.

8. The rim assembly of claim 7 wherein the means associated with the extending end of the bar and the first rim portion comprise a block fixed to the extending end of the bar, puller bolt means threadably connected through the block, and force-receiving means associated with the first rim portion so that upon rotation of the puller bolt means in one direction relative to the block, the puller bolt means contact the force-receiving 'means and pull the tire carcass portion from the first rim portion.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO.

DATED April 15, 1975 WVEHYQMS) Charles E. Grawey, et al it is certified that error aupa-xrs m the abcve-ldentlfied patent and that said Letters Patent are hereyy torrected as shown beiow' On the Title Page, Item [73], change the spelling of the assignee's corporate name from Caterpillar Tractor Company" to Caterpillar Tractor Co.

Signed and Scaled this Iwent -sec nd a 0 y 0 D fJuly1975 A tresz:

RUTH C. MASON Arresting Officer 

1. A rim assembly for a pneumatic tire carcass comprising: a first annular rim portion defining at least one guide pocket; a second annular rim portion; a guide member fixed to the second rim portion and positionable in the guide pocket to position the first and second rim portions relative to each other as they are brought together; removable means for fixing the so positioned first and second rim portions together, said rim portions when so fixed together forming a rim for said pneumatic tire carcass; and means for separating the first and second rim portions upon removal of the means for fixing the so positioned first and second rim portions together comprising a plurality of force pads fixed to the first rim portion, and a plurality of corresponding bolts threadably associated with the second rim portion and positioned so that upon rotation thereof of one direction, said bolts contact respective force pads and urge the first and second rim portions apart.
 2. A rim assembly for a pneumatic tire carcass comprising: a first annular rim portion defining at least one guide poCket; a second annular rim portion; a guide member fixed to the second rim portion and positionable in the guide pocket to position the first and second rim portions relative to each other as they are brought together; and removable means for fixing the so positioned first and second rim portions together, said rim portions when so fixed together forming a rim for said pneumatic tire carcass, wherein the first rim portion defines a second pocket, and further comprising a second guide member fixed to the second rim portion and positionable in the second pocket to position, along with the first-mentioned guide pocket and first-mentioned guide member, the first and second rim portions relative to each other as they are brought together, wherein the first and second guide pockets are defined adjacent and inwardly of the outer periphery of the first rim portion substantially 180* apart, and the first and second guide members are fixed to the second rim portion adjacent and inwardly of the outer periphery of the second rim portion, and means for separating the first and second rim portions upon removal of the means for fixing the so positioned first and second rim portions together comprising a plurality of force pads fixed to the first rim portion, and a plurality of corresponding bolts threadably associated with the second rim portion and positioned so that upon rotation thereon in one direction, said bolts contact respective force pads and urge the first and second rim portions apart.
 3. The rim assembly of claim 2 wherein the plurality of force pads comprise a pair of force pads fixed to the first rim assembly adjacent each guide pocket.
 4. The rim assembly of claim 3 wherein the first and second rim portions define outer conically-shaped surfaces having decreasing taper inward of the outer edges of the rim, and on which the tire carcass is seatable.
 5. The assembly of claim 4 and means for removing a portion of a seatable tire carcass from the first rim portion after separation of the first and second rim portions, with the tire carcass remaining on the first rim portion, comprising a bar one end of which extends into one of the pockets and which is connectable to the tire carcass therein, the other end extending outwardly of the pocket to adjacent the pair of force pads associated with that pocket, and means connected to the force pads and the end of the bar adjacent the force pads for selectively applying force to the tire carcass through the bar, to pull the tire carcass portion from the first rim portion.
 6. The rim assembly of claim 5 wherein the means connected to the force pads and the end of the bar adjacent the force pads comprise a block fixed to the end of the bar adjacent the force pads, and a pair of puller bolts threadably connected through the block and corresponding to the pair of force pads, and positioned so that upon rotation of the puller bolts in one direction, said puller bolts contact respective force pads and pull the tire carcass portion from the first rim portion.
 7. A rim assembly for a pneumatic tire carcass comprising: a first annular rim portion defining at least one guide pocket; a second annular rim portion; a guide member fixed to the second rim portion and positionable in the guide pocket to position the first and second rim portions relative to each other as they are brought together; and removable means for fixing the so positioned first and second rim portions together, said rim portions when so fixed together forming a rim for said pneumatic tire carcass, and means for removing a portion of a seated tire carcass from the first rim portion after separation of the first and second rim portions, with the tire carcass remaining on the first rim portion, comprising a bar one end of which is connectable to the tire carcass, the other end extending therefrom, and means associated with the extending end of the bar and first rim portion for selectively applying force to the bar and tire carcass through the bar to pull the tire Portion from the first rim portion.
 8. The rim assembly of claim 7 wherein the means associated with the extending end of the bar and the first rim portion comprise a block fixed to the extending end of the bar, puller bolt means threadably connected through the block, and force-receiving means associated with the first rim portion so that upon rotation of the puller bolt means in one direction relative to the block, the puller bolt means contact the force-receiving means and pull the tire carcass portion from the first rim portion. 